#title OpenFile [RCBasic Doc]
#header Function OpenFile(fileName$, mode)

Returns an ID for an open file to read or write.

Returns -1 if the file could not be opened.

Possible Text Modes
#list ul
#li TEXT_INPUT - Open a file for reading text. The file must already exist.
#li TEXT_OUTPUT - Open a new file for writing text. If the file already exist it will be overwritten.
#li TEXT_APPEND - Opens a file for appending text to the end of the file.  A file will be created if it doesn't already exist.
#li TEXT_INPUT_PLUS - Opens a file for reading and writing text.  The file must already exist.
#li TEXT_OUTPUT_PLUS - Opens a file for both reading and writing.  If the file already exist it will be overwritten.
#li TEXT_APPEND_PLUS - Opens a file for reading and appending text to the end of the file.
#/list
<br>
Possible Binary Modes
#list ul
#li BINARY_INPUT - Open a file for reading binary data. The file must already exist.
#li BINARY_OUTPUT - Open a new file for writing binary data. If the file already exist it will be overwritten.
#li BINARY_APPEND - Opens a file for appending binary data to the end of the file.  A file will be created if it doesn't already exist.
#li BINARY_INPUT_PLUS - Opens a file for reading and writing binary data.  The file must already exist.
#li BINARY_OUTPUT_PLUS - Opens a file for both reading and writing.  If the file already exist it will be overwritten.
#li BINARY_APPEND_PLUS - Opens a file for reading and appending binary data to the end of the file. 
#/list